Microbiological contamination of dried and lyophilized garlic as a potential source of food spoilage

Abstract

Garlic is valued more for its flavoring and used in a wide variety of foods. In food technology, fresh garlic is not used, but instead its processed forms, most often dried and lyophilized, are utilized. The quality and safety of the final product largely depends on their microbiological quality. This research has provided information about effect of garlic fixation methods and provided information about effect of microbiological contamination of garlic used as a spice for quality of garlic mayonnaise sauce. The authors decided to undertake studies following a report from one of the manufacturers of garlic sauces on product defects which originated in dried garlic used in the production process. Samples of garlic (n = 26) were examinated using standard cultural methods (counts of fungi, lactic acid bacteria–LAB, spore-producing Bacillus sp. and the presence of anaerobic saccharolytic and proteolytic clostridia), automated system TEMPO (total viable count, Enterobacteriaceae), immunoenzymatic method using VIDAS tests (occurrence of Salmonella sp. and Listeria monocytogenes). The number of total viable count was ranged from 3.51 to 6.85 log CFU/g. Enterobacteriaceae were detected only in one sample. Comparably low values were recorded for fungi (1.30 to 3.47 log CFU/g). The number of LAB was ranged from 2.34 to 5.49 log CFU/g. Clostridium sp. were detected in 22 samples. Salmonella sp. and Listeria monocytogenes were not detected. It was found that garlic, regardless of th preservation procedure, might be a source of contamination of garlic mayonnaise sauce especially with lactic acid bacteria and Clostridium sp. spores.